The goal of the class creator is to build a class that exposes only what’s necessary to the client programmer and keeps everything else hidden. Why? Because if it’s hidden, the client programmer can’t use it, which means that the class creator can change the hidden portion at will without worrying about the impact to anyone else.Reusing the implementation …… 29Inheritance: reusing the interface ………. 31Is-a vs. is-like-a relationships…………………. 35Interchangeable objects with polymorphism …….. 37Creating and destroying objects… 41Exception handling: dealing with errors .. 43Analysis and design …………. 44Phase 0: Make a plan………. 47Phase 1: What are we making?………………….. 48Phase 2: How will we build it? ………………….. 52Phase 3: Build the core ……. 56Phase 4: Iterate the use cases ……………….. 57